Floating probe for ultrasonic transducers

ABSTRACT

The present invention relates to a device with an ultrasonic-based probe for drilling and coring. The invention uses ultrasonic and subsonic vibrations produced by a frequency compensation coupler or free mass to produce the hammering action of a partially disengaged probe, with a relatively low axial force required. The invention can also be fitted with irrigation and aspiration capabilities. The invention can furthermore be furnished with a body sensor-feedback apparatus, which provides feedback to the operator as to the optimal frequency and power use of the generator. One embodiment of the invention also has a cooling mechanism to keep the drill or coring apparatus at an optimum temperature.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a divisional patent application of U.S.Non-Provisional patent application Ser. No. 10/729,628, filed Dec. 4,2003, which has issued as U.S. Pat. No. 7,387,612. This applicationclaims priority to U.S. Non-Provisional patent application Ser. No.10/113,141, filed Mar. 28, 2002, which has issued as U.S. Pat. No.6,689,087, which claims priority to U.S. Provisional Patent ApplicationSer. No. 60/279,427 filed Mar. 28, 2001, now abandoned, both of whichare incorporated herein in their entireties.

FIELD OF INVENTION

The present invention relates to an ultrasonic drill and corer. Moreparticularly, the invention relates to the combination of ultrasonic andsonic vibrations for drilling with a relatively low axial-force.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a depicts the components of one embodiment of the invention in anexploded fashion in the order in which the components are fittedtogether.

FIG. 1 b depicts the components of one embodiment of the invention inwhich the components shown in FIG. 1 a are fitted together.

FIG. 2 a shows a cross-sectional view of one embodiment of a fixedultrasonic probe with a cooling mechanism.

FIG. 2 b is a view of the fixed ultrasonic probe of FIG. 2 a as taken onthe line 2 b of FIG. 2 a.

FIG. 3 shows a flowchart for one embodiment of the feedback loop fordisplacement sensing of the body sensor.

FIGS. 4 a and 4 b show cross-sectional views of a section of oneembodiment of the ultrasonic floating probe that illustrates thepiezoelectric sensing crystals.

FIGS. 5 a and 5 b each show a cross-sectional view of two possiblepositions of the free mass of the ultrasonic floating probe.

FIGS. 6 a, 6 b, 6 c, and 6 d show four possible assemblies of theultrasonic floating probe.

FIG. 6 e depicts one embodiment of a multi-piece probe.

FIG. 6 f depicts one embodiment of a one-piece probe.

FIGS. 7 a and 7 b show a series of tip configurations that can be usedon the ultrasonic floating probe.

FIG. 8 shows a cross-sectional view of one embodiment of the ultrasonicfloating probe with irrigation and aspiration capabilities.

FIG. 9 illustrates the ease of use of one embodiment of the ultrasonicfloating probe.

DETAILED DESCRIPTION OF EMBODIMENTS OF THE INVENTION

Referring now to the drawings in detail, for ease of the reader, likereference numerals designate identical or corresponding parts throughoutthe views depicted in the drawings. It should be noted that a drawingdoes not depict each embodiment of the present invention; nor is each ofthe notable applications of the present invention depicted by a drawing.

The present invention uses a floating-head drilling mechanism, wherehigh frequency ultrasonic vibrations are induced by a piezoelectricstack actuator electrically connected to an ultrasonic generator andenhanced by an ultrasonic horn. The high frequency ultrasonic vibrationsare induced by the piezoelectric stack and are used to create ahammering action with both longitudinal and transverse motion beingtransferred to the floating head probe. The floating head is amechanical frequency transformer, and the drill bit operates with acombination of ultrasonic and subsonic frequencies. One example is atransformer which converts 20 kHz ultrasonic drive frequency to acombination of this high frequency drive signal and a 10-10,000 Hz sonichammering action. These values are not intended to be limiting as manyother values can be used, depending on the application. The devicepresents a low power, misalignment-tolerant device that can include aself-extracting debris process and offers hammering, chiseling, cutting,rotating, and digging capabilities. The device can further be modifiedto include irrigation and aspiration capabilities.

FIG. 1 shows the components of one embodiment of the invention in anexploded fashion in the order in which the components are fittedtogether, and FIG. 1 b shows the same components after being fittedtogether. In the embodiment shown in FIGS. 1 a and 1 b, the ultrasonicfrequencies are generated by piezoelectric ceramics or crystals (notshown) contained within housing 15. As used herein, “piezoelectricceramics” will be used to refer to piezoelectric ceramics, piezoelectriccrystals, and piezoceramics. The high frequency vibrations generated bythe ultrasonic generator (not shown) are enhanced by ultrasonic horn 64which amplifies the ultrasonic vibrations that are induced by theultrasonic generator. Resonator probe (or drill bit, floating-headprobe, or drilling mechanism), hereinafter probe 11, is inserted intohorn 64, which, in turn, is driven by the generator. Probe 11 is not,however, fixedly secured to horn 64, but allowed to partially disengagehorn 64 by using a capturing mechanism. One embodiment of the capturingmechanism is comprised of barrier member 50 and capturing member 51.

When assembled, as shown in the embodiment of FIG. 1 b, capturing member51 covers horn 64 and includes opening 42 in capturing member 51 largeenough for the tip of probe 11 to fit through. Probe 11 also has barriermember 50 that is fitted on probe 11. Thus, probe 11 is actually a“floating probe” because probe 11 partially disengages horn 64 duringthe ultrasonic frequency cycles. However, one of ordinary skill in theart will recognize that other capturing mechanisms could be used toperform the same function.

In the embodiment shown, barrier member 50 is closer to the end of probe11 that is to be inserted into horn 64 than it is to the end thatprotrudes from capturing member 51 when assembled, but could be at anypoint along probe 11. Barrier member 50 is larger than opening 42 toprevent probe 11 from disengaging horn 64 completely. Barrier member 50can be fixedly secured on probe 11 between horn 64 and capturing member51 or probe can barrier member 50 can be constructed as one integratedpiece as can be seen in FIGS. 5 a and 5 b. In addition, spring 20 can beincluded as part of the capturing mechanism and is shown in theembodiment of the present invention depicted in FIGS. 1 a and 1 b.Spring 20 is located between barrier member 50 and capturing member 51and provides extra force in pushing probe 11 back into horn 64 afterprobe 11 disengages horn 64. In one embodiment, spring 20 is compressedto one eighth of an inch (⅛″). This compression allows probe 11 to workwithout being under load, i.e., the device can be operated without auser having to exert a downward force against an object. In addition tospring 20, a bell-view washer or cantilever-type spring or spring-likematerial can be used, as can any other load mechanism known to one ofordinary skill in the art. With respect to the amount of bias in spring20, the eighth of an inch is a little more than the length of excursionof the end of probe 11, as it travels back and forth.

Capturing member 51 can be constructed in a variety of geometric shapes,two of which are shown in the drawings of this application. However, oneof ordinary skill in the art will readily appreciate that capturingmember 51 may be constructed in alternate geometric shapes so long ascapturing member 51 has opening 42 to allow probe 11 to fit through andprovides a surface to stop probe 11 from completely disengaging horn 64.

FIG. 1 also depicts the frequency compensation coupler or free mass 101that is used with this embodiment of the present invention to enhancethe conversion of the ultrasonic frequencies to subsonic frequencies.Free mass 101 is a metal disk or washer that slides on and engages probe11. As used herein, the term “free mass” is defined as any piece ofmaterial (metal or otherwise) that is not fixedly attached to any othercomponent, and is used to enhance the jack-hammering effect of thedevice for certain applications. Free mass 101 is made of almost anystrong material since it may be the weakest component of the ultrasonicprobe assembly. Examples of materials that may be used are steel(including stainless steel), titanium, or other similar metals, oralloys of these metals. However, one of ordinary skill in the art willreadily appreciate that other materials may be used with the device.

Free mass 101 is located between barrier member 50 of probe 11 and theend of probe 11 that is inserted into horn 64. Free mass 101 oscillatesbetween horn 64 and barrier member 50 of probe 11 and reduces probefrequency from a higher frequency to a lower frequency. Free mass 101acts as a modulator between the low frequency of the probe and the highfrequency of the transducer unit. Thus, free mass 101 convertsultrasonic action into subsonic action. This is desirable in someapplications because the subsonic action creates less heat and performsbetter than at ultrasonic frequencies.

In operation, as the piezoelectric ceramics rapidly expand and contract,contact horn 64, which in turn hits free mass 101, which then hits probe11, urging it forward. Probe 11 is then urged back against horn 64,either by spring 20 or some other load mechanism, or by the userexerting a downward force on the device. Free mass 101 contacts probe 11whether on its end surface (as can be seen in the embodiment of FIG. 5b) or contacts barrier member 50 on probe 11 (as can be seen in theembodiment shown in FIG. 5 a). This is repeated many times per second,producing the jack hammer-like effect of the device.

One of ordinary skill in the art should also appreciate that in additionto the materials used, free mass 101 can vary in size, shape, andweight. Exactly what size, shape, and weight chosen depends on the sizeof transducer horn 64, probe 11, and on the frequency output at whichthe device is to be operated. The diameter of free mass 101 should be atleast as great as that of the tip of horn 64 to prevent probe 11 frombeing ejected through opening 42 of capturing member 51, but smallenough not to scrape the side walls of capturing member 51. Forapplications such as drilling hardened materials, as described herein,free mass 101 is, in one embodiment, one quarter (¼) inch in diameter.For applications such as the removal of pacemaker leads, free mass 101can also be one quarter inch in diameter. However, the inner diameterand outer diameter of probe 11 is dependent on the diameter of the holesize required or the diameter of the item going through the inside ofprobe 11 such as a pacemaker lead to be removed. Thus, the size of freemass 101, in this particular application, is also a function of the leadto be removed. In another example embodiment, free mass 101 is 5 cm(five centimeters) in diameter when used for drilling and coring ice at−30° C.

It should also be appreciated that more than one free mass 101 could beemployed, as can be seen in FIG. 6 c for example. Free mass 101 allowsthe use of probes 11 of different lengths with the same frequencytransducer. As is known in the art, varying the length of probe 11 wouldnormally require modifying the transducer's frequency. The use of freemass 101 eliminates the need to tune the transducer to the differentprobe 11 lengths.

FIG. 2 a shows one embodiment of a cooling mechanism for cooling thefixed ultrasonic probe for those uses that may require cooling thedevice, e.g. some biological applications, and FIG. 2 b is a view of theultrasonic floating probe as taken on the line 2 b of FIG. 2 a. In FIGS.2 a and 2 b, piezoelectric ceramics 60, which generate the ultrasonicfrequencies that emanate to horn 64, electrical connection 80, inletport 85, exit port 86, and bolt 82 can all be seen.

In FIG. 2 b, bolt 82 can be seen, which is used to compresspiezoelectric ceramics 60. Within bolt 82 is inlet port 85 and outletport 86, running essentially the length of bolt 82. A saline solution ispumped through bolt 82 via inlet port 86, passes through and cools horn64, and then exits bolt 82 via exit port 86. In one embodiment of thiscooling mechanism, the saline coolant is pressurized to force it intobolt 82 and is attached to a vacuum to draw it out.

It should be clear to one of ordinary skill in the art that the coolingmechanism shown and described in FIGS. 2 a and 2 b may be necessary onlyfor heat-sensitive applications such as some biomedical applications.The combination of floating probe 11 with free mass 101 reduces frictionand heat such that for some applications, the use of a cooling systemwill be unnecessary. Furthermore, it should be obvious to one ofordinary skill in the art that any mechanism for cooling the device, forthose applications requiring such, may be employed.

FIG. 3 shows a flowchart of one embodiment for the feedback loop fordisplacement sensing of the body sensor feedback apparatus. The feedbackloop provides the operator with the optimal frequency and power use ofthe generator. To enable the feedback, transducer 60 is comprised of atleast two sensing piezoelectric ceramics 89, which are relatively thinand act as a body sensor, are placed near relatively thick drivingpiezoelectric ceramics 88, or driving ceramics, and are sandwichedbetween back mass 90 and front driver 99. When driving piezoelectricceramics 88 are energized, they exert a force on sensing piezoelectricceramics 89. This force is translated to an electrical signal by bodysensor 89 and sent to microprocessor 91. Buffer/attenuator 97 reducesthe voltage level of the body sensor output to a level which controlelectronics can accept. Peak detector 95 includes rectification andfilter, the output of which is proportional to the peak value of thebody sensor output. A/D source 98 is an analog to digital converter.Microprocessor 91 then calculates the resonant frequency. The requiredchange in frequency is done by frequency synthesizer 92 which generatesthe frequency signal. Switching driver 93 is a switch component thatgenerates high power square waveform which has the same frequency ofoutput as frequency synthesizer 92. Output stage driver transformer 94then boosts the voltage of the electrical signal up to the level thatcan activate driving piezoelectric ceramics 88. Output stage driver 94may or may not have impedance matching components. This device providesan instantaneous reading as to the optimal settings under which thetransducer assembly should operate. This allows the transducer assemblyto stay in tune throughout the use of the transducer. However, this bodysensor-feedback apparatus is only one embodiment, and one of ordinaryskill in the art will recognize that components could be combined orchanged with other components known to those in the art.

FIGS. 4 a and 4 b show two cross-sectional views of a section of theultrasonic floating probe that illustrates sensing piezoelectricceramics 89 in connection with the body sensor feedback apparatusdescribed and shown in FIG. 3. FIGS. 4 a and 4 b illustrate the locationand connection between driving piezoelectric ceramics 88, which producethe ultrasonic frequencies, and sensing piezoelectric ceramics 89, whichprovide the feedback to the microprocessor (not shown), in the contextof an ultrasonic device as contemplated by the present invention.Sensing piezoelectric ceramics 89 are very thin as compared to drivingpiezoelectric ceramics 88. The encased stress bolt or biasbolt 100 andhorn 64 can also be appreciated in FIGS. 4 a and 4 b. The stepped shapeof horn 64, as seen in FIG. 4 b, offers the greatest displacementmagnification when compared to other geometries of horns (for example,that of FIG. 4 a).

In one embodiment of the invention, the ultrasonic transducer assemblyoperates as a quarter wave transformer with back mass 90 acting as amechanical open-circuit, i.e., air-backed. Under this condition, thetransducer radiates most of its output energy towards probe 11 and theobject to be drilled or cored. In this embodiment, biasbolt 100 containsthe transducer assembly and is used to mount the transducer assembly andmaintain the strength of piezoelectric ceramics 60 in the stack. Whenthe transducer vibrates under high drive voltages, the tensile stressreaches levels that can fracture piezoelectric material. Biasbolt 100 istightened to induce compression at a level that slightly exceeds theexpected maximum level of tensile stress. To produce a driller/corerhead with a hollow center (e.g., when a coolant path is desired or asensor is employed), biasbolt 100 can be replaced with a threaded tube,located either at the center of the piezoelectric ceramics 60 stack orexternal to the stack, encircling the sandwiched piezoelectric ceramics60. In this embodiment, the transducer's induced displacement amplitudeis magnified mechanically by front stepped horn 64, which consists oftwo or more concentric cylinders of different diameters.

FIGS. 5 a and 5 b provide two embodiments of part of one capturingmechanism for permitting probe 11 to partially disengage horn 64. FIG. 5a shows a cross-sectional view of the section of the ultrasonic floatingprobe that engages horn 64. In this close-up view of the proximal end ofultrasonic probe 11, the tip of transducer horn 64 can be observed, andthe position of free mass 101, relative to the tip of horn 64, can alsobe seen. As shown in FIG. 5 a, free mass 101 fits over probe 11 and islocated between barrier member 50 of probe 11 and proximal end 12 ofprobe 11 that fits into horn 64. Free mass 101 can also be locatedwithin annular portion 75 of horn 64, between proximal end 12 of probe11 and horn 64 as shown in FIG. 5 b. In the embodiments shown by FIGS. 5a and 5 b, capturing member 51 can also be appreciated. Opening 42 ofcapturing member 51 is of a smaller diameter than barrier member 50 andprevents probe 11 from fully disengaging horn 64. One of ordinary skillin the art will note that other arrangements between probe 11, barriermember 50, free mass 101, and horn 64 can be envisioned and arecontemplated by the present invention. In addition, more than one freemass 101 can be used.

FIGS. 6 a through 6 f show different assemblies of the ultrasonicfloating probe device. In FIG. 6 a, a hand-held assembly with aone-piece annular plastic probe 11 inserted into horn 64 is shown, alongwith barrier member 50. It is possible to have a hand-held assembly dueto the relatively low axial pre-load required and because the device isinsensitive to alignment. This results in the device being able to beused for angled drilling and coring and is especially useful in lowgravity environments.

The device produces both longitudinal and transverse motion of probe 11.As a result of these motions, coring bit 119 creates a hole slightlylarger in diameter than that of bit 119, reducing the chance of drillbit 119 jamming during drilling and coring. Bit 119 need not be sharp,and various shaped bits 119 can be designed to take advantage of this(see FIGS. 7 a and 7 b). FIG. 6 b illustrates the same assembly as shownin FIG. 6 a except that it also shows free mass 101 as assembled in FIG.5 a, i.e., with free mass 101 located on probe 11 between horn 64 andbarrier member 50. FIG. 6 c shows the same hand-held assembly as shownin FIG. 6 b, but with the addition of second free mass 101′ locatedbetween probe 11 and horn 64. FIG. 6 d shows the same hand-held deviceas shown in FIG. 6 a, but with free mass 101 located between proximalend 12 of probe 11 and horn 64 as provided and described in FIG. 5 b. Ifthe hammering effect is to be enhanced without affecting the ultrasonicfrequency, free mass 101 should be added to the assembly.

Furthermore, FIG. 6 e depicts a two-piece or multi-piece probe, whileFIG. 6 f depicts a one-piece probe. It should be noted that in thetwo-piece construction, the pieces can be made of the same materials orcan be made of various materials such as steel and steel alloys(including stainless steel), titanium and titanium alloys, plastic, orother suitable hardened materials. It should be noted that this list isnot exhaustive and one of ordinary skill will recognize that othermaterials could be used. It should also be noted that the one-piececonstruction, as shown in FIG. 6 f, could be made of any of the samematerials.

FIGS. 7A and 7B show a series of tip configurations that can be used onthe ultrasonic floating probe according to the application. Bits 119 canbe constructed as closely-spaced, small diameter rods to allow only theselected sections of the material upon which work is being done to bechipped, or bits 119 can be smooth for slicing applications. Since bit119 and the probe (not shown) do not rotate, drilling sensors can beintegrated near bit 119 to examine and analyze the cored materialwithout the risk of mechanical damage. One or a plurality of sensors ofsensor suites can be used to examine the freshly produced surfaces,while penetrating the medium. Furthermore, the sensors can be installedin the core area to examine the cored material where emitted volatilesare sucked by a vacuum system to an analyzer (see also FIG. 8).Potential sensors include temperature, eddy-current, acoustic sensors,dielectrics, fiber optics, and others. Two specific configurations, 111and 112, are shown which have a fingered construction for coring. Thefingered configuration is particularly well-suited for coring bones, oneof the possible uses of this device. It will be obvious to one ofordinary skill in the art that any type of bit 119 configuration can beused with the present invention, depending on the application, such as,but not limited to the remaining bit 119 configurations of FIGS. 7 a and7 b.

FIG. 8 shows a cross-sectional view of one embodiment of the ultrasonicfloating probe with an irrigation and aspiration mechanism. The figureillustrates one example of a free-floating annular probe 11 with anirrigation and aspiration capability in which probe 11 is a corer. Atthe proximal end of probe 11 is adapter 109 for irrigation. Adapter 109has irrigation conduit 110, which is connected to pump head 106. Pumphead 106 is part of pump 105, which pumps irrigation fluid into probe11. The pump assembly has a number of tanks 108 which can containirrigation fluids such as saline. Each tank 108 is connected to the pumphead 106 via one or more pump conduits 113 in which the irrigation fluidis pumped through pump conduit 113 by pumps or solenoids 107, forexample. In this embodiment, there are two vacuum exits; first vacuumexit 104 for samples and second vacuum exit 102 for dust and volatiles.First vacuum exit 104 and second vacuum exit 102 comprise an aspirationunit. In the embodiment shown, second vacuum exit 102 is located withinhorn 64 and first vacuum exit 104 is located at the back of theassembly, behind piezoelectric stack 103. One of ordinary skill in theart should appreciate that other configurations in which the variousparts of the aspiration unit are located elsewhere on the device.

FIG. 9 illustrates the ease of use of the ultrasonic floating probeduring use. FIG. 9 shows user's hand 114 and is intended to demonstratethe ease of holding the invention due to the low axial force required toproduce the hammering or drilling action. The closed and lightweighthandle 115, with the elements (piezoelectric stack, horn, etc.) enclosedwithin, can be appreciated as well as probe 11. It should be apparent toone of ordinary skill in the art that probe 11 can be of differentlengths depending upon the application.

This invention, in any of the embodiments described above, can be usedin many applications. A notable application of the subject invention isfor bone grafts. The preparation of an autogenous bone graft,allografts, or other substitutes such as corralline hydroxyapatite areall useful applications of the present invention. One of the steps inbone graft is the extraction of the material to be grafted. The use ofthe present invention, with its coring and sample extraction mechanisms,is especially adapted for this purpose. Another bone graft technique isthe use of demineralized bone. Demineralized bone is a corticalallograft bone wherein the removal of surface lipids and dehydration ofthe bone has been accomplished by diverse solutions such as ethanol orhydrochloric acid. The demineralization removes acid soluble proteinsand leaves behind acid-insoluble proteins, bone growth factors, andcollagen. The bone treated in this manner can be implanted in strips orprocessed into smaller particles. It has also been suggested that ifholes are drilled into cortical allograft, it can increase the porosityof the bone by allowing a more efficient demineralization. This canresult in a bone graft that it is more osteoconductive andosteoinductive. Another use for orthopedic drilling is on hipreplacement where a hole must be drilled in the hip that is going to bereplaced in preparation for the replacement. Bone marrow samples canalso be obtained out of a person's healthy bone for typing or transplantin a less painful way that other procedures presented on the art.Another orthopedic use is for the drilling/coring for the subsequentinsertion of pins or screws after an accident or disease to put togetherand repair the bone of a patient or remove the bone cement in the caseof an implant replacement procedure.

The device assembly can also be used to drill through differentmaterials, including but not limited to, basalt, corsite, chalk, andice. Uses in mining operations and sample-taking on interplanetaryexplorations are notable applications of the present invention.

Yet another potential use of the device is as a sounding mechanism. Thehammering action provides a sounding mechanism for non-invasive probingof the ground geology to provide information about its subsurfacestructure and mechanical properties. To take advantage of thispossibility, accelerometers can be used to sense the elastic waves thatare imparted into the ground and analyze the received wavecharacteristics, providing information about, for example, soilmechanical properties, geological anisotropy, and layeredcharacteristics, as well as detect, locate, and characterize geologicalcavities, useful in such areas as construction and geologicalexcavation. The method involves transmitting elastic waves through amedium and analyzing the wave energy after interacting with the variousgeophysical features, layer characteristics, and material and groundphysical properties and flaws. As can be seen from Table 1, the elasticmoduli of soils and rocks have distinctive ranges that vary in orders ofmagnitude:

TABLE 1 Typical values of the elastic modulus for soils and rocks Soilor rock type Modulus of Elasticity, E Modulus of Elasticity, E andcondition in lb/ft² in Pa Soft clay  5K-30K 0.25K-1.5K  Wet soft clay 30K-200K 1.5K-10K  Medium Clay 10K-70K  05K-3.5K Wet medium soil100K-100K  5K-50K Stiff clay  25K-400K 1.2L-20K  Wet stiff clay  300K-1,500K 15K-75K Loose sand 200K-500K 10K-25K Medium dense sand 400K-1,200K 20K-60K Dense sand 1,000K-2,000K  50K-100K Sandstone 1.4 ×10⁸-4c10⁸    7M-20M Granite  5 × 10⁸-10 × 10⁸ 25M-50M Steel  4.2 × 10⁹200M

Although, for convenience, the method of use and corresponding apparatusof the present invention have been described hereinabove primarily withrespect to specific embodiments, it will be apparent to those skilled inthe art that many variations of this invention can be made withoutdeparting from the spirit of the invention as claimed. The descriptionspresented in those embodiments are not intended to demonstrate all ofthe possible arrangements and modifications to the design. For thoseskilled in the art, changes will be apparent that will fall within thespirit and the scope of the present invention.

1. A method comprising the steps of: providing an ultrasonic devicecomprising; a resonator probe, said resonator probe having a proximalend and a distal end; a housing; a horn fixedly secured to said housingand adapted to receive said proximal end of said resonator probe; aplurality of piezoelectric ceramics contained within said housing; acapturing mechanism, wherein said capturing mechanism permits saidresonator probe to partially disengage said horn; a free massnon-fixedly engaging said resonator probe; wherein said horn is furthercomprised of an annular portion, said free mass being positioned withinsaid annular portion of said horn, between said proximal end of saidresonator probe and said horn; and drilling in human tissue.
 2. A methodcomprising: providing an ultrasonic device comprising; a resonatorprobe, said resonator probe having a proximal end and a distal end; ahousing; a horn fixedly secured to said housing and adapted to receivesaid proximal end of said resonator probe; a plurality of piezoelectricceramics contained within said housing; a capturing member functionallyengaging said horn and at least partially enclosing said resonatorprobe, wherein said capturing member is comprised of an opening throughwhich said distal end of said resonator probe protrudes and permits saidresonator probe to partially disengage said horn; a barrier memberdisposed on said resonator probe between said horn and said capturingmember and having a diameter larger than said opening of said capturingmember; a free mass functionally engaging said resonator probe; whereinsaid horn further includes an annular portion, said free mass beingpositioned within said annular portion of said horn, between saidproximal end of said resonator probe and said horn; and drilling inhuman tissue.
 3. A method comprising: providing an ultrasonic devicecomprising; a resonator probe, said probe having a proximal end and adistal end; a housing; a plurality of piezoelectric ceramics containedwithin said housing; a horn fixedly secured to said housing and adaptedto receive said proximal end of said resonator probe; a capturingmechanism, wherein said capturing mechanism permits said resonator probeto partially disengage said horn; a free mass functionally engaging saidresonator probe; an ultrasonic generator for generating ultrasonicvibrations in said plurality of piezoelectric ceramics, wherein saidultrasonic generator is electrically connected to said plurality ofpiezoelectric ceramics; wherein said horn is further comprised of anannular portion, said free mass being positioned within said annularportion of said horn, between said proximal end of said resonator probeand said horn; and drilling in human tissue.